Use Cases

Server instances can have any number of
HTTP Listeners, both secure and non-secure. You can have both IP-address-based
and URL-host-based virtual servers.

Every virtual server can (but does not have to) have its own
list of ACLs, its own mime.types file, and its own set
of Java Web Applications.

This design gives you maximum flexibility to configure the
server for a variety of applications. The following examples discuss some
of the possible configurations available for Sun Java System Web Server 7.0 Update 1.

Default Configuration

After a new installation of the Sun Java System Web Server 7.0 Update 1 ,
you have one server instance. This server instance has just one HTTP Listener listening
on port 80 (or whatever you selected at installation) of any IP address to
which your computer is configured.

Some mechanism in your local network establishes a name-to-address
mapping for each of the addresses to which your computer is configured. In
the following example, the computer has two network interfaces: the loopback
interface (the interface that exists even without a network card) on address
127.0.0.1, and an Ethernet interface on address 10.0.0.1.

The name example.com is mapped to 10.0.0.1 via DNS. The HTTP Listener is configured
to listen on port 80 on any address to which that machine is configured ("ANY:80"
or "0.0.0.0:80").

In this configuration, connections to the following reach
the server and are served by virtual server VS1

http://127.0.0.1/ (initiated
on example.com)

http://localhost/ (initiated
on example.com)

http://example.com/

http://10.0.0.1/

Use this configuration for traditional web server use. You
do not need to add additional virtual servers or HTTP Listeners.

Secure Server

Intranet Hosting

A more complex configuration of the Sun Java System Web Server 7.0 Update 1 is
one in which the server hosts a few virtual servers for an intranet deployment.
For example, you have three internal sites where employees can look up other
users’ phone numbers, look at maps of the campus, and track the status
of their requests to the Information Services department. Previously (in this
example), these sites were hosted on three different computers that had the
names phone.example.com, maps.example.com and is.example.com mapped to them.

To minimize hardware and administrative overhead, you can
consolidate all three sites into one web server living on the machine example.com. You could set this up in two ways: using URL-host-based virtual
servers or using separate HTTP Listeners. Both have their distinct advantages
and disadvantages.

Intranet hosting using URL-host-based
virtual servers

While URL-host-based virtual servers are easy to set up, they
have the following disadvantages:

You can also set up the IP-address-based configuration with
one HTTP Listener per address:

Intranet hosting using separate
HTTP Listeners

The advantages to IP-address-based virtual servers are:

They work with older clients that do not
support the HTTP/1.1 Host header.

Providing SSL support is straightforward.

The disadvantages are:

They require configuration changes on
the host computer (configuration of real or virtual network interfaces)

They do not scale to configurations with
thousands of virtual servers

Both configurations require setting up name-to-address mappings
for the three names. In the IP-address-based configuration, each name maps
to a different address. The host machine must be set up to receive connections
on all these addresses. In the URL-host-based configuration, all names can
map to the same address, the one the machine had originally.

The configuration with multiple HTTP Listeners may give you
a minimal performance gain because the server does not have to find out the
address the request came in on. However, using multiple HTTP Listeners also
results in additional overhead (memory and scheduling) because of the additional
acceptor threads.

Mass Hosting

Mass hosting is a configuration in which you enable many low-traffic
virtual servers. For example, an ISP that hosts many low-traffic personal
home pages would fall into this category.

The virtual servers are usually URL-host-based. For example,
you can have one configuration that allows only static content, and another
one that allows static content and CGIs.